SINGAPORE: The National Environment Agency (NEA) is exploring the use of biological control methods to control the spread of dengue in Singapore.

One of the techniques involves the use of Aedes aegypti mosquitoes, which are infected with a certain bacteria, to control their population.

In this method, male Aedes aegypti mosquitoes are infected with wolbachia, which are a type of naturally occurring bacteria found in more than 60 per cent of insect species, such as butterflies and fruit flies. However, the Aedes aegypti mosquito does not carry this bacteria.
When a male mosquito infected with this bacteria mates with a female mosquito, they produce sterile eggs that do not hatch. This will then lead to a fall in the Aedes mosquito population, and help to curb the spread of dengue.

The use of such methods is being studied in countries such as Australia, Vietnam and Indonesia. NEA said it is monitoring the results of these overseas trials.

The NEA's Environment Health Institute has been carrying out laboratory research studies on this technology.

It is part of a larger programme aimed at curbing dengue transmission.

NEA has appointed a panel of local and international experts to provide advice on new ways of dengue control, and their safety concerns.

The panel is chaired by epidemiologist and entomologist Professor Duane Gubler, who is the founding director of the Program in Emerging Infectious Diseases, Duke-NUS Graduate Medical School, Singapore.

Panel members include entomologist Professor Stephen Higgs, research director of the Biosecurity Research Institute and associate vice president for research at Kansas State University; and epidemiologist Associate Professor Vernon Lee from the Saw Swee Hock School of Public Health, National University of Singapore. Professor Lee is also the head of the Singapore Armed Forces' Biodefence Centre.

This is in light of the dengue challenge Singapore faces, especially during the hotter months from June to October, traditionally the peak season for dengue transmission.

During this period, the Aedes mosquitoes breed faster. The incubation period for the dengue virus they carry, is also shorter.

The number of dengue cases has been on the rise, from 292 cases in the week of May 11-17, to 461 cases in the week of June 1-7.

SINGAPORE - Mess with us, and we may even make you sterile. This seems to be Singapore's message to the dengue-spreading mosquito as the Republic considers using biological weaponry to tame the problem.

Since last year, the Environmental Health Institute (EHI) has been carrying out laboratory studies on using Wolbachia, a naturally occurring bacteria, to help suppress the breeding of Aedes aegypti mosquitoes.

This method of biological control involves using Wolbachia-carrying male Aedes aegypti mosquitoes to mate with Aedes aegypti females to produce eggs which do not hatch.

So far, lab results seem positive and the National Environment Agency (NEA) has appointed a panel to assess the possibility of taking this a step further.

Speaking to reporters at the launch of the "Do The Mozzie Wipeout" campaign 2014 yesterday, Grace Fu, Second Minister for the Environment and Water Resources, said that Singapore was "not under any pressure" to use this method of dengue control.

"Of course, we want to fight dengue as quickly as we can, but we also want to make sure that the study is thorough and safe," she added.

EHI's studies showed that male Aedes aegypti mosquitoes here which carry the bacteria are "sterile" when they mate with female mosquitoes in the field. They are also able to compete with other males in the wild for mates.

A newly formed panel, made up of six local and foreign experts, will assess the suitability of using this method for dengue control.

The panel will convene in August. It includes experts such as Duane Gubler from the Duke-NUS Graduate Medical School and the head of the Singapore Armed Forces' Biodefence Centre, Vernon Lee.

Another panellist, Timothy Barkham, told My Paper in an e-mail interview that it was still "premature to make strong comments" about the method at this time but it "makes sense to consider all options".

"Working harder at vector control has not solved the problem, so it makes sense to consider all options, including the Wolbachia technology, which uses laboratory-bred mosquitoes to deliver the Wolbachia to wild mosquitoes," said the associate professor at the department of microbiology, National University of Singapore.

"Mosquitoes are much better at finding other mosquitoes than we are. So it sounds attractive to use them in this way."

In April, British scientist Steven Sinkins told My Paper that the bacteria do not affect humans.

"It originates from fruit flies, so even if humans are eating any fruit they are probably eating little bits of Wolbachia from the fruit flies. It doesn't do any harm," he said.

Last year, British company Oxitec successfully conducted a trial in Brazil where male mosquitoes that were genetically modified were released to produce offspring which died before reaching maturity. The mosquito population was brought down by 96 per cent over six months.

Last year saw the highest number of dengue cases on record here, with more than 22,000 cases. As of June 7 this year, about 7,000 cases have been reported.

SINGAPORE — For the first time, the National Environment Agency (NEA) is considering the use of biological control methods to limit the spread of dengue, by infecting male Aedes mosquitoes with a type of bacteria that results in females producing eggs that do not hatch.

The NEA’s Environmental Health Institute (EHI) has tested the use of the Wolbachia bacteria in the laboratory, but not in the field. A panel of experts has been set up and will convene in August to look into whether the use of the technology — which has been around since the ’60s and is being tested in Vietnam, Indonesia and Australia — is safe.

There was a record 22,170 dengue cases last year. About 7,000 cases have been reported this year, with the traditional peak period — June to October — only beginning.

Announcing the NEA’s plans at the launch of the Do The Mozzie Wipeout campaign yesterday, Second Minister for the Environment and Water Resources, Ms Grace Fu, said the Government had found the Wolbachia method to be interesting and probably applicable. “We are not under any pressure, of course. We want to fight dengue as quickly as we can, but we also want to make sure the study is thorough and safe,” she added.

Wolbachia technology involves infecting Aedes mosquitoes with Wolbachia — a naturally-occurring bacterium found in more than 60 per cent of insect species. When a male Aedes mosquito carrying Wolbachia mates with a female, the eggs produced do not hatch. The aim is to reduce the Aedes population to a level where dengue transmission cannot be sustained.

While the number of dengue cases so far this year is about 25 per cent below that of the same period last year, Ms Fu said this was still too high.

The Dengue Expert Advisory Panel consists of local and foreign experts and is led by epidemiologist and entomologist Professor Duane Gubler, founding director of the Emerging Infectious Diseases Programme at Duke-NUS Graduate Medical School.

Commenting on the Wolbachia method, Prof Gubler said in an email: “The main advantage of this and the other new methods in the pipeline is that they will control the mosquitoes that are breeding in hidden larval habitats that cannot be controlled by current methods.”

Lab studies by the EHI have shown that mosquitoes carrying Wolbachia have lower transmission potential for all dengue serotypes, as well as for the chikungunya virus. Preliminary data has also shown that male Aedes mosquitoes carrying Wolbachia can compete with wild males for female attention.

However, Monash University Dean of Science Scott O’ Neill said although the technology was powerful, releasing only male mosquitoes with the bacteria is not the most effective. Releasing both males and females infected with the bacteria would greatly reduce the ability of resident mosquitoes to transmit dengue between people, he said. He also noted that the approach Singapore was considering could be costly, as it will require continual releases of male mosquitoes to control the wild mosquito population.

Prof Gubler said other new technologies for tackling dengue could become available in the next three to five years. “These include new insecticides, genetically-modified mosquitoes (sterile male release), vaccines, antiviral drugs and therapeutic antibodies. None will likely be totally effective when used in isolation, but all show great promise if used in an integrated and synergistic programme,” he said.

Meanwhile, Ms Fu said the NEA had conducted more than 1.5 million inspections this year and would continue to focus on areas that have higher potential for dengue transmission. As of June 9, the NEA has issued 373 notices to attend court and 34 stop-work orders. There were 16 court prosecutions involving eight contractors.

GEORGE TOWN: The turtles are bouncing back to Pantai Kerachut in the Penang National Park here with the number growing to 190 between 2001 and last year with eight being the smallest number landed within a year.

Pantai Kerachut Turtle Conservation Centre chief Mansor Yobe said between 7000 and 8,000 turtle eggs were produced yearly while 50,200 hatchlings were produced from 81,142 eggs through incubation process of between 50 and 70 days at the centre during the period.
He said the sex of the hatchlings were influenced by the nests temperature, adding that female hatchlings were produced in a temperature of 30 degree Celsius and above while male hatchlings in a temperature of between 26 and 28 degree Celsius.

More female than male hatchlings are produced under controlled condition through the incubation process while between 20 and 30 per cent of the eggs were allowed to hatch naturally, he told Bernama after releasing 180 turtles, including 10 young mothers, to the sea here today.

Mansor said apart from Pantai Kerachut, turtle landings were also reported at Pantai Teluk Kampi and Teluk Ketapang in the Penang National Park as well as in Pantai Gertak Sanggul and Pasir Pandak in Teluk Kumbar, and Batu Ferringhi, but they were small in number.

Hence, the Turtle Conservation Centre, set up in 1990, would extend its operation to move turtle eggs from Gertak Sanggul and Pasir Pandak in Teluk Kumbar to Pantai Kerachut.

He said turtles usually returned to its birthplace after 20 years and 95 per cent of the turtles that landed at the centre were of Agar and green species while the rest were of the Lipas species.

"Visitors are allowed to visit the centre during the daytime. They get the opportunity to identify turtle nests, how the eggs are dug up and moved, and baby turtles being released into the sea," he said.

Meanwhile, Penang National Park deputy superintendent Zuraida Abdul Malik said the turtles’ repeated landings showed that the beaches gazetted by the Penang National Park still retained their natural landscape while replanting of trees and plants also helped attract turtles to return to lay eggs.

Those interested in having joint programmes with the centre can contact the Penang Fisheries Department at 04-6572777. -- BERNAMA

PETALING JAYA: The Klang Municipal Council (MPK) has come under heavy criticism for organising a crow-shooting event in Klang on Sunday.

A poster of the event put up by MPK has been circulating on the Internet, with many bashing the exercise which they deem as cruel.

Facebook user Dxc Kil questioned the event saying, "What purpose is this event for? Are the crows starting to affect our health/safety/environment? What's the rationale? Or is this just for fun?"
According to the poster, the event will take place from 6am to 7pm and the congregation point will be in front of the Pandamaran Hockey Stadium.

Comments also said there were many crows there as the place was not clean.

"We should stop littering and dumping food which crows eat. This causes more crows to breed, Shooting them is not a solution," said Warren Wu.

When contacted, an MPK officer said the exercise was initiated due to public complaints that there were too many crows around.

The MPK officer also said that a press conference would be held at the hockey stadium at 9am Sunday to explain the exercise to the media.

THE El Nino weather phenomenon, which can cause global famines, floods and even wars, has a 90% chance of striking this year, according to the latest forecast from Europe.

El Nino begins as a giant pool of warm water swelling in the eastern tropical Pacific that sets off a chain reaction of weather events around the world, some devastating and some beneficial.

India is expected to be the first to suffer, with weaker monsoon rains undermining the nation’s fragile food supply, followed by further scorching droughts in Australia and collapsing fisheries off South America.
But some regions could benefit, in particular the United States, where El Nino is seen as the “great wet hope”, bringing rains that could break the searing drought in the west.

The knock-on effects can impact even more widely, from cutting global gold prices to making England’s World Cup foot­ballers sweat a little more.

The latest prediction is from the European Centre for Medium-range Weather Forecasts, which is considered one of the most reliable of the 15 or so prediction centres around the world.

“It is very much odds-on for an event,” said Tim Stockdale, principal scientist at the centre, who said 90% of their scenarios deliver an El Nino.

“The amount of warm water in the Pacific is now significant, perhaps the biggest since the 1997-98 event.”

That El Nino was the biggest in a century, producing the hottest year on record at the time and major global impacts, including a mass die-off of ­corals.

“But what is very much unknown at this stage is ­whether this year’s El Nino will be a small event, a ­moderate event – that’s most likely – or a really major event,” said Stockdale, adding that the picture will become clearer in the next month or two.

“It is which way the winds blow that determines what happens next and there is always a random element to the winds.”

The movement of hot, rain-bringing water to the eastern Pacific ramps up the risk of downpours in nations flanking that side of the great ocean, while the normally damp western flank dries out.

Governments, commodity traders, insurers and aid groups such as the Red Cross and World Food Programme all monitor developments closely. Water conservation and food stockpiling is already underway in some countries.

Prof Axel Timmermann, an oceanographer at the University of Hawaii, argues that a major El Nino is more likely than not because of the specific pattern of winds and warm water being seen in the Pacific: “In the past, such alignments have always triggered strong El Nino events.”

El Nino events occur every five years or so, peaking in December and the first, and potentially greatest, human impacts are felt in India.

The reliance of its one billion-strong population on the monsoon, which usually sweeps up over the southern tip of the sub-continent around June 1, has led its monitoring to be dubbed “the most important weather forecast in the world”.

This year, it has got off to a delayed start, with the first week’s rains 40% below ­average.

“El Nino could be quite ­devastating for agriculture and the water supply in India,” said Dr Nick Klingaman, an El Nino expert at the University of Reading.

Research last month showed the global impact of El Nino events on food supplies, with corn, rice and wheat yield much lower than normal, though soybean harvests tend to rise.

While food production has improved in the last year, El Nino could reverse that trend, according to Leo Abruzzese, global forecasting director for the Economist Intelligence Unit.

“It may reduce agricultural output over the next few years, which could weigh on global food security.”

Drought linked to the 2007 El Nino led to a surge in food prices in 2008 that sparked riots in countries as far afield as Egypt, Cameroon and Haiti.

After India, El Nino’s impacts roll east and officials in Cebu, the Philippines’ second city, have urged all households to save water to reduce the impact of the drier weather due by the end of June.

In Malaysia, the national water authority is preparing for a dry spell of up to 18 months.

The hot, dry skies will then track to Australia, where 2013 was its hottest year.

Andrew Watkins, manager of climate prediction services at the Australian Bureau of Meteorology, said: “El Nino is one of the largest influences on Australia’s climate.”

However, in the US, El Nino holds out the prospect of relief for the western states and nowhere is more desperate for rain than California.

The entire state is in severe or extreme drought, after receiving barely a quarter of its annual rainfall, and communities have been under water rations since March, ordinarily still the rainy ­season.

A strong El Nino would bring rain, typically double the annual average in southern California.

“I commonly refer to El Nino as the great wet hope,” said Bill Patzert, a climate ­scientist at Nasa’s Jet Propulsion Laboratory in California.

“Everyone in the west has their fingers crossed because we are bone dry.”

However, big El Ninos like the 1997-98 event – what Patzert calls “Godzillas” – are rare and forecasters at the US government’s climate prediction centre said on June 5 that time was running out for a significant El Nino to be set in train. — Guardian News & Media 2014